Anthropic disrupts malicious use of Claude AI for weapons and cyber espionage

Anthropic says it has identified and disrupted attempts to use its AI model for "malicious activity" that could support biological and conventional weapons development.

The company's AI model Claude was also used in a Russia-linked cyber espionage campaign and by an Iranian propaganda institution, according to Anthropic's latest threat intelligence report.

The cases of concern detected over the past eight months ranged from fake dating apps and hotel Wifi scams, to surveillance built to identify dissidents.

The revelations come after warnings from a top safety researcher at Anthropic about AI's potential risks to humanity.

Anthropic has also accused Chinese AI firms of trying to replicate Claude's capabilities.

The company published its latest threat intelligence report, external on Thursday, saying it did so because it believes it has "a responsibility to disclose malicious misuse of our services".

The lengthy report lists cases in which suspected state-sponsored groups, criminals, spyware vendors, state propaganda institutions and politically motivated individuals misused its technology.

"Malicious use" of its Claude Haiku, Sonnet, and Opus models was disrupted between December 2025 and August 2026, it said.

None of the misuse cases involved Claude Fable or the powerful Mythos-class models, with the exception of one instance of distillation - the process for training smaller AI models using larger, more expensive models.

As well as detecting the use of its models for cyber and influence operations, surveillance, scams and fraud and weapon development, Anthropic said it had blocked scientists who used its AI in ways that could support biological weapons development.

The report highlighted "five case studies of actors using our models in ways that could support biological weapons development".

Biological misuse, it said, is "one of the most serious risks of frontier AI model". Without the correct safeguards, such capabilities "could have catastrophic consequences", Anthropic said.

"The same information that can be used to develop a biological weapon could also be used to develop, for example, a vaccine or a cure for a disease," Anthropic said.

Jacob Klein, the head of threat intelligence at Anthropic, told the New York Times, external it was "an incredibly nuanced situation".

You are not seeing someone in a comic book kind of way say, 'Hey, I want to build a biological weapon to kill everybody,'" he said.

The report also noted six cases where Claude was used "to develop software for conventional weapons, including firearms, missiles, armed drones, bombs, and other munitions, as well as the targeting and control systems that operate them".